The object of the invention is an apparatus for producing tobacco industry material strips of substantially homogeneous geometric shapes and a method of producing tobacco industry material strips of substantially homogeneous geometric shapes.

Commonly known in the tobacco industry are 'heat not burn' smoking articles which are heated instead of being burned like traditional cigarettes so that they do not release tar substances and other agents which are harmful to smokers. „Heat not burn” cigarettes can be manufactured of multiple segments which act as a filter or segments to be heated. The segments to be heated may contain nicotine, glycerine, flavouring, aromatic substances or other additives improving the smoking effect. Segments acting as a filter can contain both flavouring and aromatic substances.

Both types of segments, i.e. filtering and heated segments, can be manufactured of various types of organic or inorganic materials. For example, it can be tobacco, processed tobacco, derivatives of tobacco, starch, cellulose or other fibrous materials. In order to prepare such segments, the base material must be properly prepared by forming a strand of material, soaking it in the target solution if it does not itself contain the required substances, forming it into a continuous rod and cutting it into segments of required length. Prior to forming, the filling material is subjected to various processing operations, for example, it can be cut into strips or small pieces or creped so that it is then easier to shape the continuous rod and to achieve a better degree of segment filling with the material. In addition, the resistance to smoke flow through such a segment or the degree of filtration is increased.

In the prior art, there are various methods for processing the filler material used to manufacture segments from which rod-like elements are formed.

EP 2713778 discloses a method of manufacturing a rod-like element of a smoking material such as reconstituted tobacco. A strand of material undergoes a crimping operation substantially parallel to longitudinal edges of the strand, after which it is wrapped in a wrapping material and shaped into a continuous rod to be cut into segments.

The document US 4000748 discloses a process and an apparatus for crushing a sheet of reconstituted tobacco. The material is cut into small strips and simultaneously creped as it passes between a pair of interlocking disc sets.

US 4889143 discloses a cigarette comprising a plurality of substantially longitudinally extending strands obtained from a shredded creped sheet of reconstituted tobacco. Such strands are formed into a rod shape and then wrapped with a paper wrapper. The continuous rod thus formed is then cut into smaller sections of regular length. In order to achieve proper density and resistance to flow through the resulting rod-like elements, the material strands travelling on the paper wrapper are moved at a slower speed than the strands exiting the creping apparatus. The difference in these speeds causes the strands to be placed on the wrapper in a wrinkled, corrugated manner thus increasing the degree of filling of the formed continuous rod.

The document GB 803472 discloses a cigarette filter filled with thin strips of fibrous material having holes on its surface or distorted edges. The filling of the filter part of the cigarette with such strips is intended to increase the filtration rate, the deposition of harmful substances in the filter, and to increase the resistance to smoke flow through the filter part of the cigarette. WO 2020013339 discloses a 'heat not burn' product with a segment to be heated, filled with strips of base material which release aromatic and flavouring compounds when heated.

The problem to be solved by the present invention is to provide an apparatus and a method for producing tobacco industry material strips with substantially homogeneous geometric shapes. Such strips are to constitute a filling material of a final tobacco industry product. Substantially homogeneous geometric shapes within the meaning of the present invention mean in this context strips of material being uniform/homogeneous in shape and dimensions. Nevertheless, it should be noted that the uniformity of shape does not mean that all the strips have the same shape and proportions, but the uniformity of shape also means that strips of two different types, with two different dimensions or shape proportions, in a certain quantitative proportion are obtained in the output product. In this case, the uniformity of shape means the conformity of shape with the specification which may indicate that the product contains, for example, 85% of strips of the first type (first dimensions) and 15% of strips of the second type (second dimensions), with substantially no strips of other sizes and shapes. To put it in perspective, this effect is quite different from the effect obtained in the shredding process used in the paper industry where the aim is to obtain strips of material that are as varied in shape and size as possible so that it is impossible to reconstruct a damaged part of the material.

It was observed that the non-uniformity of geometric shapes of the tobacco industry material strips in the known solutions resulted from non-synchronisation or variations in the speed of individual components of the apparatus producing the strips and thus in the stages of the production method: feeding, perforating and cutting. As a result of the above-described non-synchronisation, there are differences in the tension of the continuous strand of material being fed, which translates into a reduction in the repeatability of conditions in which the cutting process takes place (and thus in the homogeneity/uniformity of the tobacco industry material strips). With too little tension and corrugation of the material strand, the produced strips may be too wide, and with too much tension the strips may be too narrow. Uniform geometrical shapes of the tobacco industry material strips are achieved in the present invention by synchronising the speed of feeding, perforating and cutting the processed, continuous material strand. As a result, it is possible to achieve a uniform tension of the processed continuous material strand and thus reproducible conditions in the cutting process and uniform/homogeneous tobacco material strips.

The object of the invention is an apparatus for producing tobacco industry material strips of substantially homogeneous geometric shapes from at least one continuous strand of tobacco industry material comprising: at least one feeding apparatus for feeding the continuous strand of material and at least one perforating apparatus for making perforations in the form of cuts on the continuous strand of material at a first linear speed, situated downstream of the feeding apparatus. The apparatus further comprises a first conveyor for conveying, at a second linear speed, at least one continuous strand of material with cuts, situated downstream of the perforating apparatus, and a rotary cutting head for cutting at a third linear speed, situated transversely to the direction of conveying the strand of material, downstream of the conveyor. The apparatus is characterised by being provided with a controller adjusting the first linear speed of the perforating apparatus, the second linear speed of the conveyor and the third linear speed of the rotary cutting head relative to one another to maintain the desired geometric shape of the tobacco industry material strips cut by the cutting head.

Preferably, in the apparatus according to the invention, the second linear speed of the first conveyor is dependent on the third linear speed of the rotary cutting head.

Preferably, in the apparatus according to the invention, the second linear speed of the first conveyor is dependent on the physical properties of the final product. Preferably, in the apparatus according to the invention, the first linear speed of the perforating apparatus is dependent on the third linear speed of the rotary cutting head.

Preferably, in the apparatus according to the invention, the perforating apparatus is adapted to make cuts along the strand of material, substantially parallel to the conveying direction.

Preferably, the apparatus according to the invention has a second conveyor arranged above the first conveyor so that the distance between these conveyors narrows when viewed in the conveying direction.

Preferably, in the apparatus according to the invention, the rotary cutting head is in the form of a drum situated with its rotational axis transversely to the conveying direction of the strand of material and has a plurality of cutting knives arranged on the circumference of the drum.

Preferably, in the apparatus according to the invention, between the feeding apparatus and the perforating apparatus there is situated a tensioner adapted to keep the tension of the strand of material .

Preferably, in the apparatus according to the invention, the feeding apparatus feeds the continuous strand of material at a fourth linear speed.

Preferably, in the apparatus according to the invention, the controller adjusts the fourth linear speed of the feeding apparatus.

The object of the invention is also a method of producing tobacco industry material strips of substantially homogeneous geometric shapes from at least one continuous strand of tobacco industry material comprising steps wherein: the continuous strand of material is fed by means of the feeding apparatus to the perforating apparatus and the continuous strand of material is cut by means of the perforating apparatus operating at the first linear speed. Furthermore, in the method according to the invention, the continuous strand of material is conveyed at the second linear speed in the direction of the rotary cutting head, by means of a conveyor, and the continuous strand of material is cut by means of the rotary cutting head operating at the third linear speed into tobacco industry material strips, the rotary cutting head being situated transversely to the direction of conveying the strand of material downstream of the conveyor. The method is characterised in that the first linear speed of the perforating apparatus, the second linear speed of the conveyor, and the third linear speed of the rotary cutting head are adjusted relative to one another by means of a controller to maintain the desired geometric shape of the tobacco material strips.

Preferably, in the method according to the invention, the strand of material is cut lengthwise by means of the perforating apparatus.

Preferably, in the method according to the invention, multiple strands of material are clamped by means of two conveyors situated one above the other before the strand of material is cut by means of the rotary cutting head.

Preferably, in the method according to the invention, at least one strand of incised material is cut into tobacco industry material strips transversely to the conveying direction.

Preferably, in the method according to the invention, the fourth linear speed at which the strand of material is fed by the feeding apparatus is adjusted relative to the first linear speed of the perforating apparatus, the second linear speed of the conveyor, and the third linear speed of the rotary cutting head by means of the controller.

An advantage of the apparatus and the method according to the invention is that high repeatability of dimensions and shapes of the tobacco industry material strips is provided. In other words, the apparatus and the method according to the invention make it possible to obtain uniform geometric shapes of the tobacco industry material strips used as a filling of the final tobacco product. A direct technical effect obtained by the present invention is to ensure a high quality of cutting and perforation, while maintaining the continuity and the stability of the process, irrespective of the number of strands of material being processed. This results in a further technical effect of increasing the homogeneity/uniformity of the tobacco industry material strips, thus ensuring the homogeneity of filling of the formed rod-like article and thus of the final tobacco industry product.

The object of the invention is described in more detail with reference to the embodiment shown in the drawing in which:

Fig. 1 shows an apparatus for producing tobacco industry material strips from at least one continuous strand of tobacco industry material;

Fig.2 shows the apparatus for producing tobacco industry material strips from at least one continuous strand of tobacco industry material, with a speed synchronisation system visible;

Fig. 3 shows the first embodiment of a perforating apparatus;

Fig. 4 shows a pattern of cuts created on a strand of material obtained by means of the perforating apparatus according to the first embodiment;

Fig. 5 shows a cutting head according to the first embodiment;

Fig. 6 shows the second embodiment of the perforating apparatus;

Fig. 7 shows a pattern of cuts created on a strand of material obtained by means of the perforating apparatus according to the second embodiment;

Fig. 8 shows the cutting head according to the second embodiment;

Fig. 1 shows an apparatus 1 for producing tobacco industry material strips from at least one continuous strand of tobacco industry material 2, 2', 2". The material used in the apparatus according to the invention may be a material of organic or inorganic origin. For example, it may be a strand of material made of tobacco, reconstituted tobacco, derivatives of tobacco, paper, cellulose, fibrous materials, corn starch, plastic, cotton or any other material suitable for the use in the tobacco industry in the manufacture of articles for smoking, heating or inhalation.

The apparatus 1 shown in Fig.1 comprises three modules A, B , C, each module respectively comprising a feeding apparatus 3, 3', 3" for feeding a strand of material 2, 2', 2" to a perforating apparatus 4, 4', 4". The perforating apparatus 4, 4', 4" makes cuts along the strand of material 2, 2', 2", substantially parallel to the conveying direction T. The strand of material 2, 2', 2" is supplied to the apparatus 1 in the form of a roll 12, 12', 12" which is mounted on a rotary shaft13, 13', 13" driven by a drive which is not shown in the figure. The strand of material 2, 2', 2" unwound from the roll 12, 12', 12" is guided by a tensioner 10, 10', 10" in the form of a plurality of rollers and self-aligning arms. The task of the tensioner 10, 10', 10" is to hold the strand of material 2, 2', 2" in a proper tension. It must not be too loose or too tense, as it may break. In addition, the tensioner 10, 10', 10" has to maintain the proper tension of the strand of material 2, 2', 2" when synchronising the linear speed Vr, Vr', Vr" of the roll 12, 12', 12" and the linear speed Vp, Vp', Vp" of the perforating apparatus 4, 4', 4". From the tensioner 10, 10', 10", the strand of material 2, 2', 2" passes through the perforating apparatus 4, 4', 4" comprising two rollers - the first roller 14, 14', 14" and the second roller 15, 15', 15" where the perforation in the form of cuts on the strand of material 2, 2', 2" is performed. Embodiments of the perforating apparatus and the cuts are described in more detail in further figures. After the strand of material 2, 2', 2" has exited with the perforation made, it is fed to the conveyor 5 positioned downstream of the perforating apparatus 4, 4', 4". In this embodiment, the apparatus 1 comprises three modules A, B and C. First, the strand of material 2" from the module C is fed onto the conveyor 5, then the strand of material 2' from the module B and the last strand of material 2 from the module A are added. The strands 2, 2', 2" thus conveyed are gradually pressed from above by the second conveyor 7 which is situated above the first conveyor 5 so that the distance between the conveyors gradually narrows, thus the conveyed strands 2, 2', 2" are compressed. Subsequently, the strands 2, 2', 2" are cut into small strips of tobacco industry material 11 by means of a cutting head 6. The cutting head 6 has the form of a drum 8 with a rotational axis X, situated at the very exit of the conveyors 5 and 7, with the rotational axis X transverse to the direction T of conveying the strands of material 2, 2', 2". Embodiments of the cutting head are shown in further Figs. 7-8.

In order to ensure a high perforation quality, the accuracy of cutting of the strands of material 2, 2', 2" and to maintain the repeatability of dimensions of the tobacco industry material strips 11 into which the strand 2, 2', 2" is cut, the feeding unit 3, 3', 3" is synchronized with the perforating apparatus 4, 4', 4", and the perforating apparatus 4, 4', 4" is synchronized with the conveyor 5 which is synchronized with the cutting head 6. The synchronization is to be understood as the interdependence of linear speeds of the synchronized units so that the linear speed of the conveyed strands 2, 2', 2" is substantially the same over the entire length of the unwound strands 2, 2', 2".

The linear speed Vr, Vr', Vr" of the roll 12, 12', 12" with the strand of material 2, 2', 2" of the feeding apparatus

3, 3', 3" is dependent on the linear speed Vp, Vp', Vp" of the rollers 14, 14', 14" and 15, 15', 15" of the perforating apparatus 4, 4', 4". The rollers 14, 14', 14", 15, 15', 15" of the perforating apparatus 4, 4', 4" generally should not rotate faster or slower so that the linear speed of the perforating edges coming into contact with the strand of material 2, 2', 2" is not different from the linear speed VI of the strand of material 2, 2', 2" passing through the perforating apparatus 4, 4', 4"; this means that the linear speed Vp, Vp', Vp" on the circumference of the rollers 14, 14', 14", 15, 15', 15" of the perforating apparatus 4, 4', 4" should be substantially equal to the linear speed VI of the strand of material 2, 2', 2". The linear speed Vr, Vr', Vr", the linear speed Vp, Vp', Vp" and thus the linear speed VI of the strand of material 2, 2', 2" are adjusted by the controller 20. Thus a variation by the controller 20 in the rotational speed of any of the apparatuses causes a variation in its linear speed as follows from the formula v = co * r, where v - denotes the linear speed, co - denotes the angular speed, r- denotes the radius of the rotated object. If the controller 20 increases the rotational speed cop, cop', cop' of the rollers 14, 14', 14", 15, 15', 15" of the perforating apparatus 4, 4', 4" thereby increasing the linear speed Vp, Vp', Vp" of the rollers 14, 14', 14", 15, 15', 15", this will also increase the linear speed Vr, Vr', Vr" of the roll 12, 12', 12". The same applies to a reduction in speed - if the controller 20 reduces the linear speed Vp, Vp', Vp" of the rollers 14, 14', 14", 15, 15', 15" of the perforating apparatus

4, 4', 4" then it will also reduce the linear speed Vr, Vr', Vr" of the roll 12, 12', 12". Since the strand of material 2, 2', 2" wound on the roll 12, 12', 12" gradually wears out during production, at the same time causing the diameter of the roll 12, 12', 12" to decrease, this forces a gradual increase of its rotational speed cor, cor', cor" by the controller 20 in order to maintain the linear speed Vr, Vr', Vr" and thus the linear speed VI of the strand of material 2, 2', 2'" at a set value. The linear speed Vr, Vr', Vr" is calculated on the basis of the current diameter of the roll 12, 12', 12" and the rotational speed cor, cor', cor", which is controlled by a sensor (not shown in fig.) and adjusted to the linear speed Vp, Vp', Vp" of the rollers 14, 14', 14", 15, 15', 15" of the perforating apparatus 4, 4', 4". The controller 20 may be a PLC, a computer or any other device controlling, calculating and synchronising the rotational or linear speeds known in the state of the art. Since the perforating apparatus 4, 4', 4" is synchronized with the linear speed Vt of the first conveyor 5, the strand of material 2, 2', 2" coming out of the perforating apparatus 4, 4', 4" should have its linear speed VI adjusted by the controller 20 in such a way that substantially the linear speed VI of the strand 2, 2', 2" is close to the linear speed Vt of the conveyor 5. Too high or too low linear speed VI of the strand of material 2, 2', 2" coming out of the perforating apparatus 4, 4', 4" relative to the linear speed Vt of the conveyor 5 may cause the strand of material 2, 2', 2" to corrugate on the conveyor 5 or to stretch and pull the strand of material 2, 2', 2" out of the rollers 14, 14', 14", and 15, 15', 15" of the perforating apparatus 4, 4', 4". Such a phenomenon will result in uneven perforations, stretching or tearing of the material 2, 2', 2", and thus, after final cutting, in the formation of tobacco industry material strips 11 of various dimensions. Therefore, the introduction of a controller 20 synchronising the speeds of individual subassemblies leads to an increase in the uniformity of the shape of the strips in the finished product.

The conveyor 5 is synchronized with the cutting head 6 and, more precisely, the linear speed Vt of the conveyor 5 is synchronized with the linear speed Vc of the cutting head 6 by the controller 20 so that the cutting of the strips takes place with uniform dimensions of the strips to be cut.

If the cutting head 6 is the master unit in the apparatus 1 , then the linear speed Vt of the conveyor 5 will depend on the linear speed Vc of the cutting head 6. Conversely, if the conveyor 5 is the master unit, then the linear speed Vc of the cutting head 6 will depend on the linear speed Vt of the conveyor 5. In the discussed embodiment, the controller 20 will adjust the rotational speeds cop, cop', cop" of the rollers 14, 14', 14", 15, 15', 15" of the perforating apparatus 4, 4', 4"as well as the rotational speed cor, cor', cor" of the roll 12, 12', 12" of the feeding unit 3, 3', 3" so as to adjust the linear speeds VI of the strand 2 , 2', 2" in this area of the apparatus to the linear speed Vt of the conveyor 5. The linear speed Vc of the rotary cutting head 6 and the linear speed Vt of the conveyor 5 are controlled by the controller 20. These relationships are strictly dependent on the target dimensions of the strips into which the strand of material 2 , 2', 2" is to be cut. If, as a result of a change in specification or due to the need to adapt the width of the strips to the selected specification, the width of the cut strips of tobacco industry material 11 has to be increased, then the controller 20 has to increase the linear speed Vt of the conveyor 6 while maintaining the current linear speed Vc of the cutting head 6 if it is the master unit. If, on the other hand, the conveyor 5 is the master unit, then, in order to increase the width of the cut strips of tobacco industry material 11 , the controller 20 will have to decrease the linear speed Vc of the cutting head 6 while maintaining the current linear speed Vt of the conveyor 5.

As mentioned above, the entire speed synchronisation/adjustment process is carried out by the control system 20 which controls and adjusts directly or indirectly rotational speeds and linear speeds of individual units. The control system collects and sends information from the drive units, for example: servo motors, DC motors, induction motors, squirrel cage motors, and sensors, for example: encoders, position sensors, proximity sensors, in order to set the appropriate speeds on the individual units. The above-mentioned group of devices is an open group and may also include other devices not listed, but meeting the given requirements.

For example, when it is necessary or desirable to reduce the width of the cut tobacco industry material strips 11 while maintaining the current linear speed Vc of the cutting head 6, the operator enters the desired parameters for the dimensions of the tobacco industry material strips 11 on the control panel 16. The information is transmitted to the control system 20 which then increases the linear speed Vt of the conveyor 5. As the conveyor 5 is synchronized with the perforating apparatus 4, 4', 4", the linear speed Vp, Vp', Vp" of the rollers 14, 14', 14" and 15, 15', 15" is automatically increased by the controller 20, and thus by synchronization with the feeding apparatus 3, 3', 3" the controller 20 increases the linear speed Vr, Vr', Vr" of the roll 12, 12', 12" so as to maintain the linear speed VI of the material strand constant with the material strand 2, 2', 2" in all units of the apparatus 1 , on the conveyor 5, in the perforating apparatus 4, 4', 4" and in the feeding apparatus 3, 3', 3".

Where the apparatus 1 comprises more than one module A, B, C, it is important to maintain the same linear speed VI of the material strands 2, 2', 2" on each of the modules A, B, C starting from the feeding apparatus through the perforating apparatus 4, 4', 4" to the conveyor 5 which is common to all modules A, B, C. The advantage of using more than one module A, B, C is that the process continuity is ensured, i.e. it is not required to stop the entire machine when a strand of material 2, 2', 2" in one of the modules A, B, C runs out. Moreover, the addition of further modules increases the efficiency of the machine, as strips from more strands of material are cut at the same time. In an embodiment wherein there is more than one module A, B, C, when one of the modules A, B, C is disconnected following, for example, the need to load a new roll with the continuous strand of material 2", the disconnected module (one of the modules A, B, C) is no longer synchronized with the remaining modules A, B, C. When the module A, B, C is put back into operation, i.e., for example, when a new roll of the strand of material 2, 2', 2" is loaded, the controller 20 automatically synchronizes the speed of the module A, B, C, which has been put back into operation, with the other working modules A, B, C. The speed VI of the newly fed strand will be synchronized with the linear speed Vc of the cutting head 6 and adjusted to the speeds VI of the other strands that have been fed continuously.

It is also possible to provide an embodiment of the apparatus 1 for producing tobacco industry material strips wherein the feeding apparatus 3, 3', 3" will not be equipped with a drive. In that case, the strand of material 2, 2', 2" situated on the roll 12, 12;, 12" will be unwound by means of the perforating apparatus 4, 4', 4", more precisely by the rotational movement of the rollers 14, 14', 14"', and 15, 15', 15'". In order to keep the strand of material 2, 2', 2" in tension and to prevent excessive unwinding, a brake, for example a friction brake, may be used to introduce resistance on the roll 13, 13', 13" during the rotation.

In such arrangement, the controller 20 will only synchronize/adjust rotational speeds and linear speeds of the cutting head 6, the conveyor 5 and the perforating apparatus 4, 4', 4".

Fig.3 shows the perforating apparatus 4 in the first embodiment. It comprises the first roller 14 and the second roller 15 arranged parallel to each other so that they can substantially contact each other with their outer surfaces 17 and 18. The rollers 14 and 15 rotate in opposite directions R1 and R2. The second roller 15 has perforating knives 19 situated parallel to each other at intervals R along the axis S1. The interval R is equal to the maximum length of the tobacco industry material strips 11 into which the strand of material 2 is cut. In this embodiment, the cutting edge of the perforating knives 19 is serrated, but a smooth blade without serrations may also be used. The length L of the perforating knives 19 is dependent on the length of the cut to be made on the strand of material 2. When the strand of material 2 is inserted between the rollers 14 and 15, it is cut by the perforating knives 19 along the length L at the intervals R. The knives 19 cut the strand of material 2 by plunging on its other side into grooves 21 which are situated on the second roller 14 parallel to each other at the intervals R along the rotational axis S2 of the roller 14. The depth of the grooves 21 is slightly greater than the height of the knife 19.

After the strand of material 2 has exited the perforating apparatus 4, the perforation remains on the strand of material 2 in an arrangement as shown in Fig. 4. On the strand, there are cuts 22 arranged parallel to the longitudinal edges of the strand 2 at the intervals R having the length L. Depending on the required dimensions of the tobacco industry material strips 11 into which the strand 2 will be finally cut, the intervals R may be reduced or increased, thus causing a reduction or an increase in the final length of the tobacco industry material strips 11 .

Fig. 5 shows the process of cutting the strand of material 2 with the applied perforation of the final tobacco industry material strips 11 by means of the cutting head 6. The cutting head 6 is in the form of a drum 8 having knives 9 positioned parallel to the axis of rotation X and protruding beyond the outer outline of the drum 8. The number of the knives 9 arranged on the drum depends on its diameter, the rotational speed, the width into which the tobacco industry material strips 11 are to be cut and the drive power of the head. Since the cutting head 6 is driven by a drive (not shown in Fig.) and rotates in the direction R3, each of the knives 9 rotates in the same direction at the same rotational speed. During the insertion of the strand of material 2 with the applied cuts 22, the knife 9 of the cutting head cuts the material 2 substantially perpendicular to its longitudinal edges at the places indicated by the broken line 23, causing the strand of material 2 to be cut into a plurality of small strips of tobacco industry material 11. The length of the tobacco industry material strips 11 is defined by the intervals R between the cuts made during the perforation, while the width of the tobacco industry material strips 11 depends on the linear speed Vt of the conveyor 5 and the linear speed Vc of the cutting head 6 calculated from its rotational speed wc. If it is necessary or desirable to increase the width of the cut tobacco industry material strips 11 then the operator enters the desired value on the control panel 16. The controller 20 will automatically increase the linear speed Vt of the conveyor 5 while keeping the linear speed Vc of the cutting head constant, or, depending on which unit is the master unit, decrease the linear speed Vc of the cutting head 6 while keeping the linear speed Vt of the conveyor 5 constant.

Fig. 6 shows the perforating apparatus 4a in the second embodiment. It comprises two rollers 14a and 15a arranged parallel and tangentially to each other. Outside the outline of the outer surface of the roller 15a, there protrude perforating knives 19a which are arranged substantially transversely to the direction of rotation R2a of the roller 15a. The intervals R between the knives 19a define the final length of the tobacco industry material strips 11 into which the strand 2 is cut. The strand 2 inserted between the oppositely rotating rollers 14a and 15a is cut by the knives 19a over a length L substantially perpendicular to the longitudinal edges of the strand of material 2. The knives 19a, during the cutting, pass to the other side of the strand 2 and may plunge into the grooves 21 a which are arranged on the roller 14a in the same configuration as the knives 19a on the roller 15a. After exiting the perforating apparatus 4a, the perforation on the strand of material 2 remains as shown in Fig. 7. On the strand 2, there are applied cuts 22a situated parallel to one another and substantially perpendicular to the longitudinal edges of the strand 2 at the intervals R having the length L. In this embodiment, the intervals R are constant, which means that the length of the final tobacco industry material strips 11 of the strand is not varied. The strand 2, after exiting the perforating apparatus 4a, is delivered to the cutting head 6a by the conveyor 5 and cut at the cutting points 23a into the final tobacco industry material strips 11 , as shown in detail in Fig. 8.

Fig.8 shows the second embodiment of the cutting head 6a when cutting the strand of material 2 with applied cuts 22a.The cutting head 6a is in the form of a roller 23 with mounted circular cutting knives 9a arranged at intervals parallel to one another along the rotational axis Xa. The cutting edge of the circular knives 9a may be serrated or smooth without serration. Since the cutting head 6a is driven by a drive (not shown in Fig.) and rotates in the direction R3a, each of the knives rotates in the same direction at substantially the same rotational speed. The strand of material 2 having cuts 22a made in the perforating apparatus 4a is supplied by the conveyor 5 perpendicular to the rotational axis Xa. The circular knives 9a are arranged relative to one another at intervals F which define the width into which the tobacco industry material strips 11 will be cut. The length of the tobacco industry material strips 11 is equal to the intervals R among the cuts 22a arranged on the strand 2. In this embodiment of the cutting head 6a, it is not possible to automatically vary the width of the tobacco industry material strips 11 to be cut. Regardless of the linear speed Vc of the cutting head 6a, the width will only depend on the interval F among the circular knives 9a. In order to vary the width of cutting the tobacco industry material strips 11, it is necessary to change the roller 23 of the cutting head 6a to such which will have circular knives situated at intervals F equal to the desired width dimension of the tobacco industry material strips 11.